{ bootstrap ? import <nixpkgs> {} }:
let

  pin = builtins.fromJSON (builtins.readFile ./nixpkgs.json);
  src = bootstrap.fetchFromGitHub {
    owner = "NixOS";
    repo  = "nixpkgs";
    inherit (pin) rev sha256;
  };
  pkgs = import src {};
  build = pkgs.haskellPackages.callCabal2nix "wtf-build-please" ./. {};

in
  { wtf-build-please = build; }
